Spermine synthase, animal (IPR015576)

Short name: Spermine_synthase_animal

Overlapping homologous superfamilies

Family relationships


The polyamines putrescine, spermidine and spermine represent a group of naturally occurring compounds exerting a bewildering number of biological effects. Their biosynthesis is accomplished by a concerted action of four different enzymes: ornithine decarboxylase, adenosylmethionine decarboxylase, spermidine synthase and spermine synthase. The development and introduction of specific inhibitors to the biosynthetic enzymes of the polyamines have revealed that an undisturbed synthesis of the polyamines is a prerequisite for animal cell proliferation to occur [PMID: 1930914].

The human spermine synthase gene is involved in polyamine metabolism and is localised to the Xp22 region [PMID: 9467015]. From isolated and sequenced cDNA clones that encode human spermine synthase EC:, it was found the total length of the sequenced cDNA was 1,612 nucleotides, containing an open reading frame encoding a polypeptide chain of 368 amino acids. All other sequenced peptide fragments of human and bovine spermine synthase proteins could be located within the coding region derived from the cDNA. Sequence comparisons between human spermine synthase and spermidine synthases from bacterial and mammalian sources revealed a nearly complete lack of similarity between the primary structures of these two enzymes catalyzing almost identical reactions indicating they could have evolved separately [PMID: 7546290].

GO terms

Biological Process

GO:0006597 spermine biosynthetic process

Molecular Function

GO:0016768 spermine synthase activity

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.